Component Tests and General Diagnostics
Starter Circuit TroubleshootingNOTE:
- Air temperature must be between 59 and 100 °F (15 and 38 °C) during this procedure.
- After this test, or any subsequent repair, reset the engine control module (ECM) to clear any diagnostic trouble codes (DTCs).
- The battery must be in good condition and fully charged.
- If you disconnect the battery, do the ECM idle learn procedure.
Recommended Procedure:
- Use a starter system tester.
- Connect and operate the equipment in accordance with the manufacturer's instructions,
Alternate Procedure
1. Hook up the following equipment:
- Ammeter, 0 - 400 A
- Voltmeter, 0 - 20 V (accurate within 0.1 volt)
- Tachometer, 0 - 1,200 rpm
2. Remove the No. 17 (15 A) fuse from the under-dash fuse/relay box.
3. With the clutch pedal pressed, turn the ignition switch to start (111).
Did the starter crank the engine normally?
YES - The starting system is OK. Reinstall the No. 17 (15 A) fuse in the under-dash fuse/relay box.
NO - Go to step 4.
4. Check the battery condition. Check electrical connections at the battery, the negative battery cable to body, the engine ground cables, and the starter for looseness and corrosion. Then try starting the engine again.
Did the starter crank the engine?
YES - Repairing the loose connection fixed the problem. The starting system is now OK. Reinstall the No. 17 (15 A) fuse in the under-dash fuse/relay box.
NO - If the starter will not crank the engine at all, go to step 5. If it cranks the engine erratically or too slowly, go to step 7. If it won't disengage from the flywheel ring gear when you release the key, check for the following until you find the cause.
- Solenoid plunger and switch malfunction
- Dirty drive gear or damaged overrunning clutch
5. Make sure the transmission is in Neutral, then disconnect the starter subharness 1P connector (A) from the engine wire harness 1P connector (B). Connect a jumper wire from the battery positive terminal to the starter subharness 1P connector.
Did the starter crank the engine?
YES - Go to step 6.
NO - Check the BLK/WHT wire between the starter subharness 1P connector and the starter. If the wire is OK, remove the starter, and repair or replace as necessary.
6. Check the following items in the order listed until you find the open circuit.
- Check the BLK/WHT wire and connectors between the under-dash fuse/relay box and the ignition switch, and between the under-dash fuse/relay box and the starter.
- Check the ignition switch.
- Check the clutch interlock switch and connector.
- Check the starter cut relay.
- Check LT GRN wire between the starter cut relay/under-dash fuse/relay box and the clutch interlock switch.
- Check the BLK wire between the clutch interlock switch and G501.
7. Check the cranking voltage and current draw.
Is the cranking voltage greater than or equal to 8.7 V and is the current draw less than or equal to 230 A?
YES - Go to step 8.
NO - Replace the starter, or remove and disassemble it, and check these items until you find the cause.
- Open circuit in starter armature commutator segments
- Drag in the starter
- Shorted armature winding
- Excessive drag in the engine
8. Check the engine speed while cranking the engine.
Is the engine speed above 100 rpm?
YES - Go to step 9.
NO - Replace the starter, or remove and disassemble it, and check for the following until you find the cause.
- Excessively worn starter brushes
- Open circuit in commutator brushes
- Dirty or damaged helical splines or drive gear
- Faulty drive gear clutch
9. Remove the starter, and inspect its drive gear and the flywheel ring gear for damage. Replace any damaged parts.
10. When all repairs are done, reinstall the No. 17 (15 A) fuse in the under-dash fuse/relay box.